This invention relates to an anchor for a seat belt for a seat for a mobile vehicle such as medium or heavy-duty truck, the vehicle with the seat belt anchor installed, and the process of back fitting an existing vehicle with a seat with a seat belt. The seat belt anchor may be installed in a vehicle cab either during manufacture of the vehicle or in the after market. The anchor provides the surface area required for providing the strength required by Federal Law and fits around existing components of the cab.